The invention relates to a system for reversibly storing digital data on a plurality of parallel and uniform magnetic tape tracks under execution of a frame-based error protection encoding operation embodied in a product code that has first code words each defined in a single track and second code words defined in a recurrent cycle around all of said plurality of tracks. Such a system has been disclosed in European Patent Application EP A1 437 865, corresponding to now issued U.S. Pat. No. 5,467,360 (PHN 13213) assigned to the same assignee, and herein incorporated by reference. The reference relates to the Philips Digital Compact Cassette (DCC) system for digital magnetic tape recording, which is intended for high quality audio at about 16 bits per sample. Magnetic tape is extremely suitable for many purposes for reason of its facility by reversible recording, and would be an advantageous vehicle for data and program recording in an environment of personal computers, multimedia applications, education, and various others. In consequence, a need has started to be felt to upgrade the DCC format for applicability in those environments that impose extremely strict standards as regards reliability on various levels.